Manufacture of direct dyeing disazo-dyestuffs



Patented June 16, 1931 I UNITED STATES PATIENT OFFICE CARL METTLER, F BAsEL, SWITZERLAND, ASTSIGNOR fro THE FIRM or J. n. GEIGY s. 5.}

" or BASEL, SWITZERLAND I I V I MANUFACTURE OF DIRECT DYEING nrsazo-nynsmurrs 3 3 diam'ino -4: 4- dihydroxy-diphenylsulphone has hitherto not been used in the dyestulf 'industry, notwithstanding that the parent materials therefor, for instance 5 4: 4 dihyclroxy-diphenylsulphone and 3 3 'dinitro-4 1-dihydroxydiphenylsulphone, are

easily accessible (Annalen der Chemie, Vol. 147, page 59,.vol. 1'2'2, page B-erichte der deutschen chemischen Gesellschaft, vol. 40, page 644, and vol 8, page 1060).

According to this invention, 3 3 -diamino-' 4: 1-dihydroxydiphenylsulphone as such is tetrazotized and coupled with two molecular I O uHaNm s 0 3H proportions of an arylated 2-amino-5-naphthol-7-sulphonic acid to produce disazo-dyestuffs which, when dyed on cotton with addiion of metal salts, such as for example copper sulphate, yield violet dyeings of an excellent fastness to light, highcolour strength and good fastness to washing. Under an alkylated 2-amino-5-naphthol-7-sulphonic acid there is to be understood a phenylor substituted phenyl-2-amino-5-naphthol-7-sulphonic acid.

Instead of3 3-diamino-4i t-dihydroxydiphenylsulphone as such there may also be used substitution products thereof, in which there are contained 'in the nucleus one or more methyl-groups or halogen'atoms. By coupling such substitution products with 'arylated 2-amino-5-naphthol-7-sulphonic ac ids, dyestufi's of similar properties are obtained. V

The following examples illustrate the invention, the parts being by weight V 7 Example 1 28 parts of 3 3-diamino-4: 4'+dihydroxydiphenylsulphone of the formula HzN N H:

No Drawing. Application filed October 23, 1929, Serial No. 401,978, and. in'Germany November 15, 1928 are tetrazotized in presence of ice by means, of hydrochloric acid andltparts ofsodium nitrite and the tetrazo product is coupled with 64 parts of phenyl 2 am'ino 5-naphthol- 7-sulphonic acid in a solution-alkaline with sodium carbonate. .After stirring for 24;

hours, heating and salting out, there is ob-I tained'a dyestutf which, when dry, is a dark bronze powder,'freely soluble in water to a CaHs . Jams 5 6H I on p v 0H 7 so2 OH It dyes cotton directly Bordeaux rosetin-ts, becoming violet on treatment with copper sulphate. In order to exhaust the dyebath it is advantageous-to dye together with cap per sulphate. The dyeing isof good colour strength, very fast to light and of-good fastness to washing. i 7 It is also possible to'va'ry the working so as to obtain directly thecopper salt of the dyestufi in pure and finished form and to thenu'se same for dyeing with addition of soda. 7 Analogou's dyestuffs are obtained when there is s'ubstituted for the phenyl-2-aminos5- naplithGI-T-sulphonic acid, the ortho-, meta: and phonic acid, or the.para-Salicyl-Q-aminobf naphthol-7-sulphonic acid, .or the. para-1 V 'anisyl-2-amino-5snaphthol-7-sulphonicacid.

In the last-named case, cotton-is dyedbluish vio1et .1.- may f In the Chemischen Zentralblatt 1912, vol;- 2, page 251, there is described a dinitro-orthooxytolylsulphone which is to be regarded as para-tolyl 2-Iamino-5-naphthol-7?sul 1() hydroxy 5 5 dimethyl-diphenylsulphone,

3: 3 -dinitro-4L: 4='-dihydroxy-5 5'-dimethyldiphenylsulphone of the formula:

Hosol-Q By reducing this compound, there is easily obtained a solution of?) 3-diamino-4L: lJ-diwhich is tetrazotized as described in'E'xample I 1 and coupled with'phenyl-2;amino-5-naphthus obtained has the formula 0H3 .1- 'om,

and is a dark bronzepowder which dissolves freely in water toa blue violet solution and insulphuric acid to a. red violet solution. lVith copper sulphate on cotton it dyes violet.

tints of great colour strength, of excellent fastness to llght and good fastness to wash-' mg.

In this example, the 3 3-diamin0-4 4'-di hydroxy- 5 5 dimethyl diphenylsulphone can be replaced by the corresponding nuclear chloroor halogen substitution product.

WVhat I claim is 1. A process for the manufacture of direct dyeing disazo-dyestuffs, consisting in tetrazotizing 3 :r3-diamino-{l: 4 dihydr0Xy-diphenylsulphones and coupling the tetrazo-prodnot with two molecular proportions of arylated 2-.amino-5-naphthol-7-sulphonic acids.

2. A process for the manufacture of direct dyeing disazo-dyestulfs', consisting in 'tetrazotizing 3 3-diamino-l: 4E-dihydr' Xydiphenylsulphones having a nuclear methylsubstituent and coupling the tetrazo-productv with two molecularproportionsof'arylated Q-amino-5-naphthol-7-sulphonic acids.

3. As new articles of manufacture, the direct dyeing disazo-dyestuffs obtained by tetrazotizing 3 3-diamino-4 :F-dihydroxy-diphenylsulphones and coupling the tetrazoproduct with two molecular proportions of arylated 2-amino-5-naphthol 7-sulphonic acids, said dyestuffs'being soluble in water to V a blue-violet and in sulphuric acid to a redviolet coloration and dyeing cotton'directly with copper sulphate violet tints of good colour strength, veryfast to light and of good fastness to washing. A i r In witness whereof I have hereunto signed my name this 7th day of October, 1929.

CARL METTLER.

thol-7-sulphonic acid; The disazo-dyestuff V 

